Female officers have little incentive to try the infantry course. The women, who remain anonymous under Pentagon research policy, volunteer despite the risk of injury and the delay in starting specialized training in their own job fields.

The potential payoff is only personal satisfaction, a pat on the back for furthering the research, and a spot in history as the first woman to pass what many consider the toughest school in the Marine Corps.

Last fall, one of the first two women officers trying the infantry course hung in for more than a week before stress fractures forced her out.

2nd Lt. Kerry Olinger, formerly of San Diego, said several women in her basic officer course plan to volunteer for infantry training.

“There is a female in one of our platoons who could definitely gut-check the CET (combat endurance test),” Olinger said.

Allowing qualified women to serve on equal footing with male combatants would be a huge step forward, and one long overdue, she added.

“It’s been happening for the past decade, regardless of what Congress has allowed or the Marine Corps has officially allowed as doctrine. It’s time to be recognized.”

The test

When Capt. Patrick Skehan, instructor adviser, walks into the room crowded with lieutenants and combat gear, no one will meet his eye. The room is dead silent, the students nerve-racked over what’s to come.

He was too in 2007, when he did the course. Some of the rumors about it are bizarre. “I thought there was a puppy-killing station,” he recalled. “Some think they have to knife fight.”

The lieutenants will face only what they encountered during the six-month basic officer course. Land navigation, weaponry, martial arts. Just all at once in a gauntlet of undetermined length.

The uncertainty is a kind of stress common in combat. How they cope with it is part of the human dimension of warfare.

The lieutenants are trucked into the woods before dawn. They step into the darkness disoriented and isolated, forbidden from speaking to one another. The only sounds are the clink of rifle muzzles, the drone of crickets. A crescent moon and an occasional fire fly are the only lights.

One forgets his protractor, making it almost impossible to orient himself efficiently. Several head for miles in the wrong direction.

“You can be in great physical shape, but if you can’t do land navigation, it doesn’t matter how many Tough Mudders you’ve done,” Cuomo says, referring to the civilian race.

2nd Lt. Thomas Stipanov graduated from Francis Parker High School and Yale University. His parents are both lawyers. Growing up in a military town like San Diego, Stipanov had his heart set on the Marine Corps from a young age.

When he was 3, he made a crayon drawing that said “iwanttobeamarine,” no spacing, no punctuation.

“The warrior ethos and culture of achievement resonates with my personal values,” he said before the course began. “I wanted to serve.”

Stipanov is not a big guy. Just 5-foot-7, 160 pounds. His aggressiveness and intensity helped him hold his own as a nose tackle on the defensive line, playing varsity football in school.